Improvement in vacuum-brakes for railway cars



ROBERT JqwlLsom.

improvement in Vacuum Brake for Railway Cars.

No. 120,922. Patented Nov-14,1871,

Wfi {S 3 S I q v v v Q Q 6/7 $1 #3121) UNITED STATES PATENT QFFIGE.

ROBERT J. WILSON, OF PITTSBURG, PENNSYLVANIA.

IMPROVEMENT IN VACUUM-BRAKES FOR RAILWAY CARS.

Specification forming part of Letters Patent No. 120,922, dated November14, 1871.

To all whom itmay concern:

Be it known that I, ROBERT J. WILsoN, of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a certain new anduseful Improvement in Vacuum-Brake for Railway Cars; and I do herebydeclare that the following is a full, clear, and exact descriptionthereof, reference being had to the accompanying drawing and to theletters of reference marked thereon.

The nature of my invention consists in Open atin g car-brakes throughthe medium of a cylinder, piston, and pipes connected with avacuum-chamber, which is connected with an airpump operated by anengine, said air-pump and pipes connected with the cylinder beingprovided with valves, which are so arranged as to be under the controlof the engineer, who may at hispleasure open the valve of the pipescommunicating with the cylinder and thereby bring the brakes to bear onthe wheels of the railway cars.

To enable others skilled in the art to make and use my invention, I willproceed to describe its construction and operation.

In the accompanying drawing which forms part of my specification, Figure1 is a side elevation of two trucks for railway cars, said trucks beingprovided with my improvement for operating or applying the brakes to thewheels through the. medium of the apparatus hereinafter described. Fig.2 is an inverted view of the same.

A andBare two trucks for railway cars, and are of ordinary construction.To the under side of the truck A is secured a chamber, 0, to which areattached pipes c i j, which are connected with pipes Z Zthroughthemedium of couplings 'n n. The pipes l l are connected with the cyl'inder D, as shown in Fig.2. The chamber 0 is connected with an air-pump,c, through the medium of a pipe, k. The "air-pump is provided withvalvesf, and its plunger is operated through the medium of a cylinder,gfwhich receives its steam from the boiler of the locomotive andis soarranged as to be under the control of the engineer. The area of thepiston-head should be less than the area of the piston-head of theair-pump 0, so that when a partial vacuum is formed in the chamber 0 themotor used for operating the plunger of the air-pump will not havesufficient power to operate the air-pump e after the desired vacuum isobtained. The cylinder orengine 9 and air-pump 6 may be constructed inany of the known forms suitable for combining them with the locomotiveof railway cars, and they may be arranged with relation to thelocomotive in any desired manner. The pipes i ij are provided with avalve, k, which valve is used for the purpose of cutting ofi'communication between the cylinder D and the vacuum-chamber G. Thisvalve is arranged so as to be under the control of the operator, and maybe opened and closed at his pleasure. To the piston-head of the cylinderD is attached a piston-rod, m, to which is connected levers, chains, orother devices for operating the car-brakes, which may be of any knownconstruction suitable for being operated by rods, levers, or chains whenconnected to the piston-rod m of the cylinder D.

As the construction and arrangement of the several parts of my inventionwill readily be understood from the foregoing description and byreference to the accompanying drawing, I will, therefore, proceed todescribe its operation, which is as follows: Steam from thelocomotive-boiler is admitted to the cylinder or engine g, which willoperate the air-pump c and thereby form a partial vacuum in the chamber0. Now, by opening the valve k of the pipes i 'ij,'the air oratmospheric pressure will act on the end of the piston-head of thecylinder D, carrying it for ward toward the vacuum-chamber O, and withit will carry forward the piston-rod m, which, drawing upon the levers,rods, or chains connected with the brakes, will thereby bring the brakesto bear upon the wheels of the cars.

By reversing the action of the air-pump the piston-head of the cylinderD may be thrown back, thereby relieving the draft on the rods, levers,or chains connected to the piston-rod m, thus taking the force off thebrakes.

It will readily be seen by the skilled mechanic that the force broughtto bear on the brakes will depend upon the area of the piston-head ofthe cylinder D, and the size of the whole used for operating car-brakesthrough vacuum-chamber (3,2tir-p1u11pe, and cylinder or the medium of aVacuum, as hereinbefore deengine g. scribed.

Having thus described my invention, What I ROBT. J. WILSON. claim is-The combination of air-pump e, vacuum-chem- Witnesses:

ber (J, and cylinder D, said parts being con- A. G. J oHNs'roN, nectedthrough the medium of pipes, and the Jums J. JOHNSTON. (122)

